Why doesnt it work

When i download the app throught the website or the APK I can not run anything is this because the phone isnt compatible?

Generally speaking, there are 3 architectures for phones, arm (armeabi-v7a) the 32 bit arm aechitecture, arm64(arm64-v8a), and the x86 (Intel based chips). Usually apps are built for specific architectures because they contain certain architecture’s libraries to run.

If it isn’t built for your architecture it will say that your phone isn’t compatible. Can I know your phone and the app you’re trying to install?

Usually developers may just push 2 updates at once for two arechitectures or a universal apk that contains library for all of these architectures

What exactly do you mean by this? Any error message? Got any screenshots that show the problem?

Its not compatible i found out why

Then why? Can you tell us?

I have an app in Android store

It’s not visible in Fdroid

So I need to give apk to fdroid ?

You need to submit it to F-Droid. See the FAQ for guidance: